Aryl phosphoric acid halides



m (came-O mcarrying outthe re Patented Feb. 16

UNITED STATE wherein R represents a te represents a halogen and n and n are integers stantially non-flammable, possess pronounced fungicidal properties, and nate wood and the like as gus, molds, etc. They are slowly hydrolyzed by water to form the corresponding aryl phosphoric ,acids, which also possess fungicidal properties. The new compounds also serve as chemical agents for the preparation of a variety of neutral aryl and aryl-alkyl-phosphates which are useful as plasticizers in nitrocellulose, cellulose acetate, and cellulose ether compositions. Certain compounds having the above formula are disclosed but not claimed in my co-pending application, Serial'Nfo. 2,585, flied January 19, 1935, of whichthe present application is a continuation in part.

The aryl phosphoric a above general-formula are prepared by heating a para-tertiaryalkylphenol thereof-to a reaction temperature with at least 0.5, preferably between equavalents of a phosphor phorusoxychloride or oxybromide. A para-ten, tiaryalkylphenol, rather than its alkali metal salt,

compounds herein disclosed have the action there is a tendency t s PATENT. oFFicE ARYL PHOSPHORIO ACID HALIDES Shailer L. Bass, Midland, Mich, assignor to The Dow Chemical Company, Midland, Mich a corporation of Michigan No Drawing. Application July Serial No. 90,379

11 Claims. (Cl. 260-9920) certain new aryl phosto react further with the phenolic reactant, promethod of making the ducing thereby a triaryl phosphate instead of the desired aryl phosphoric acid halide. This tendency becomes more pronounced as the ratio of phosphorus oxyhaiide to the phenolic reactant 5 is reduced or the reaction temperature is raised. Accordingly, in preparing a monoaryl phosphoric acid dihalide I prefer to employ 1.5 or more moles of phosphorus oxyhalide per mole of the phenolic reactant and in preparing a diaryl phosphoric acid 10 monohalide I preferably use between 0.75 and 1.5 moles of phosphorus oxyhalide per mole of the phenolic reactant. In either case, the reaction is carried out at the lowest temperature which will permit smooth and reasonably ra When using phosphorus oxychloride in the reaction, such temperature is usually between and C. although higher temperatures, e. g. 0., may be used. Phosphorus oxybromide may be reacted at somewhat lower temperatures e. g. 20

In preparin phoric acid monortiary alkyl radical, X

having the sum of 3. Such compounds are submay be used to impregprotection against fung a para-tertiaryalkylphenyl phosor di-halide, a mixture of a para-tertiaryalkylphenoland phosphorus oxychloride, or oxybromide, in the proportions stated 25 above, is heated with stirring under reflux at temperatures within the range just stated until hydrogen halide is no longer evolved from the mixture. The products are thenseparated by distilling the mixture under vacuum. Ordinarily, 30 both an aryl phosphoricacid dihalideand the corresponding monohalide are obtained from a given reaction, but by regulating the proportions of the reactants and the reaction temperature, as hereinbefore explained, the reaction may be controlled so as to produce the desired product in major proportion.

The following examples illustrate several ways in which. the principle of the invention has been 40 applied, but are not to be construed as limiting the invention.

cid halides having the or alkali metal salt 0.75 and '4, molecular us oxyhalide, e. g. phosis preferred as the phenolic'reactant since the- 35 'free' phenol is usually mo such purpose; it reacts a salt, and hydrogen halide re readily available for s smoothly as does'the evolved when using the dichloride phosphoric horic acid 1 Example I v A mixture of 1501 grams (10 mole) ofparaertiary-butylphenol, 2301 grams (15 mole) of for the aryl phosphoric acid halide initially formed phosphorus oxychloride, and 15 grams of an- HIN! pid reaction. 15

2 hydrous magnesium chloride was heated at temperatures varying from to C. for 2.5 hours, i.-e. until the evolution of hydrogen chloride from the mixture had substantially ceased.

The hot mixture was blown with air to remove hydrogen chloride and then fractionally distilled under vacuum. There was collected 1706 grams of a liquid fraction whichdistilled over at176 C. under 10 millimeters pressure. This material boiled at -153 C. under 6 millimeters pressure and had the specific gravity 1.244 at 20 C. It was substantially pure para-tertiarybutylphenyl phosphoric acid dichloride having the formula During said distillation there was also separated 191 grams of another fraction of material, distilling' between and 310 C. under 10 millimeters pressure, which solidified on cooling. This material was recrystallized from petroleum ether, whereby 27.5 grams of substantially} pure di- (para tertiarybutylphenyl) phosphoric acid monochloride was separated as colorless'crystalsmelting at 100.5-101.5 C. Said product-has the formula roo 1 (OHzhU O Example 2 A mixture of 328.2 grams (2 mols) of paratertiaryamylphenol and 1027.2 grams (6.7 mols) of phosphorus oxychloride was heated under re- I During the distillation there was also obtained 54 grams of a viscous yellow liquid distilling at term peratures above the boiling point of para-ten tiaryamylphenyl phosphoric dichloride. This high boiling liquid material included the compound di-(para-tertiaryamylphenyl) phosphoric acid monochloride, having the formula Example 3 A mixture of 412 grams (2 mols) of para-tertiaryoctylphenol of freezing point 81 C. (also known as para-diisobutylphenol) and 1224 grams (8 mols) of phosphorus oxychloride was heated und'er reflux with stirring at temperatures varying from 70 to 100 C. for about 20 hours. The

mixture was then fractionally distilled, whereb 414 grams (1.28 mols) of substantially pure paratertiaryoctylphenyl phosphoric acid dichloride, distilling at temperatures between 197 and203 C. at 13 millimeters pressure, and 90.8 grams of a higher boiling material, which started distilling at 203 C. under 13 millimeters pressure and was completely distilled at 220 C. under 10 millimeters pressure, were obtained. The para-tertiaryoctylphenyl phosphoric acid dichloride is a clear colorless liquid, boiling at approximately 192-195 C. under 10 millimeters pressure and having the specific gravity 1.159 at 25 C. It has the formula mc- Mam-E O-POOh The higher boiling material collected from the distillation was a viscous yellow liquid which fumed on exposure to moist air. It contained the compound, di-(para-tertiaryoctylphenyl) phosphoric acid monochloride having the formula V CH: CH!

Other para-tertiaryalkylphenyl phosphoric acid halides may be prepared by similar procedure.

, For instance, para-tertiarybutylphenol may be reacted with phosphorus oxybromide to form the compounds, para-tertiarybutylphenyl phosphoric acid dibromide and di- (para-tertiarybutylphenyl) phosphoric acid monobromide; a para-tertiaryhexylphenol may be reacted with phosphorus oxybromide to form the corresponding mono- (para-tertiaryhexylphenyD- and di-(para-tertiaryhexylphenyl) -phosphoric acid bromides; -etc. Other modes of applying the principle of the invention may be employed instead of those explained, change being made as regards the method or compounds herein disclosed, provided the steps or compounds stated by any of the following claims or the equivalent of such stated steps or compounds be employed.

'1 therefore particularly point out and distinctly claim as my'invention:

1. An aryl phosphoric acid halide having the formula v (BO-Liam.

nOo-ie-x 2. An aryl phosphoric acid dihalide having the 191 wherein It represents a tertiary alkyl radical and X a halogen selected from the class consisting of chlorine and bromine,

V 3. A diaryl phosphoric acid monohalide having the formula T wherein R represents a tertiary alkyl radical and a halogen-selected from the class consisting of chlorine and bromine.

4, An aryl phosphoric acid chloride having the formula wherein n and n are integers having the sum of 3.

wherein n and n are integers having the sum oi. 3.

6. Para-tertiarybutylphenyl phosphoric acid dichloride, a colorless liquid boiling at approximateiy 150-158' C. at 6 millimeters pressure and having the specific gravity 1.244 at 20 C.

'l. Di-(para-tertiarybutylphenyl) phosphoric acid mono-chloride, a crystalline compound melting at approximately loos-101.5 C.

8. Para tertiaryamylphenyl phosphoric acid dichloride, a liquid compound boiling at approximately 174 C. at 10 millimeters pressure and having the specific gravity 1.159 at 25 C. p

9. The method oi making a para-tei'tiaryalkylphenyl phosphoric acid halide which comprises reacting a phosphorus oxyhalide selected from the class consisting of phosphorus oxychloride and phosphorus oxyhromide with not more than twice its molecular equivalent of a compound selected from the class consisting of. a para- 1 tertiaryalkylphenols and their alkali metal salts.

10. The method oi making a para-tertiarybutylphenyl phosphoric acid chloride which comprises reacting phosphorus oxychloride with not more than twice its molecular equivalent of paratertiarybutylphenol. p

' 11. The method of making a. para-tertiaryamylphenyl phosphoric acid chloride which comprises reacting phosphorus oxychloride with not more than twice its molecular equivalent of paratertiaryamylphenol.

BHAILER L. BASS. 

